{"cve":"CVE-2021-31930","nvd":{"published":"2021-05-19T15:15:08.850","modified":"2026-06-17T03:52:30.870","status":"Modified","description":"Persistent cross-site scripting (XSS) in the web interface of Concerto through 2.3.6 allows an unauthenticated remote attacker to introduce arbitrary JavaScript by injecting an XSS payload into the First Name or Last Name parameter upon registration. When a privileged user attempts to delete the account, the XSS payload will be executed.","cvss_v4":null,"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N","score":6.1},"cwes":["CWE-79"],"references":["https://github.com/concerto/concerto/pull/1558","https://github.com/concerto/concerto/security/advisories","https://github.com/concerto/concerto/pull/1558","https://github.com/concerto/concerto/security/advisories"],"products":["concerto-signage:concerto"],"source":"nvd","synced_at":"2026-10-19T21:18:09.669877188+00:00"},"epss":{"cve":"CVE-2021-31930","score":0.00921,"percentile":0.60328,"date":"2026-10-31"},"kev":null,"osv":[],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}